Visible light degradation of reactive black-42 by novel Sr/Ag-TiO2@g-C3N4 photocatalyst: RSM optimization, reaction kinetics and pathways.
Visible light degradation of reactive black-42 by novel Sr/Ag-TiO2@g-C3N4 photocatalyst: RSM optimization, reaction kinetics and pathways.
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DOI：
10.1016/j.saa.2019.117870
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发表时间：
2019-11
期刊：
影响因子：
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通讯作者：
Xueyu Wei;Xiaoping Xu;Xiaofan Yang;Jiyuan Li;Zhigang Liu
中科院分区：
文献类型：
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作者：
Xueyu Wei;Xiaoping Xu;Xiaofan Yang;Jiyuan Li;Zhigang Liu
采用溶胶-凝胶法和水热法制备了一种新型的锶/银-二氧化钛@g-C3N4(SAT-C)复合催化剂。制备的催化剂具有较好的表征性能。掺杂的银和锶纳米粒子起到了电子转移桥的作用，银的表面等离子体共振效应显着提高了电荷分离效率，增强了对活性黑(RB-42)降解的可见光响应。由于异质结积分电场的存在以及TiO2和g-C3N4杂化产生的光响应的叠加，增强了光生电荷分离，其中，Sr/Ag-Ti02@g-C3N4复合材料对Rb-42的光催化降解活性显著提高。此外，利用响应面方法(RSM)系统地评价了各种操作参数对光催化过程的影响。在最佳条件下([RB-42]0=0.20 mg/L L，[SAT-C]0=0.2 mg/g L，pH=94.5，t=0.40分钟)，RB-42的降解率最高，为95.6%。在最佳条件下，对RB-42的降解动力学进行了研究。此外，通过LC/ESI-MS分析确定了RB-42的主要降解产物。
A novel Sr/Ag-TiO2@g-C3N4(SAT-C) composite catalyst was fabricated through a sol-gel method followed by hydrothermal process. The prepared catalyst was characterized well. The doped Ag and Sr nanoparticles played the crucial role as an electron transfer bridge and the surface plasmon resonance effect of Ag remarkably improved the charge separation efficiency and enhanced visible-light response towards reactive black (RB-42) degradation. The enhanced photogenerated charge separation resulted from the existed integrated electric field of heterojunction and the superposed light response from hybridization of TiO2and g-C3N4, Sr/Ag-TiO2@g-C3N4composites exhibited remarkably improved photocatalytic activities for degrading RB-42. Furthermore, the effect of various operational parameters on the photocatalytic process was systematically evaluated by using response surface methodology (RSM). The maximum degradation efficiency (95.6%) was observed under the optimal conditions ([RB-42]0= 20 mg/ L, [SAT-C]0= 0.2 g/ L, pH = 4.5 andt= 40 min) for RB-42. The RB-42 degradation kinetics was well studied under the optimal conditions. In addition, the main degradation products of RB-42 were identified by the LC/ESI-MS analysis.